7T MRI system

Product Specifications/Features/Salient Characteristics Required Minimum Specifications The purchase includes acquisition of a new 7T MRI system, turnkey installation of the system within the FMRIF Center, and the trade-in and removal of an existing Siemens 7T Plus MRI. Replacement or upgraded MRI System: The characteristics of an MRI system suitable for this application should meet the following performance requirements: A 7T actively shielded magnet Local gradient with (at least) 40 cm free, available internal diameter providing with 200 mT/m max amplitude and 900 T/m/s slew rate. A RF receiver system with at least 64-channels, with two 32-channel P-ports available for RF coil connections RF receivers providing digital sampling bandwidth of (at least) 1 MHz, sampling with at least 16-bit resolution and providing user access to raw (i.e. pre-image reconstruction) MR sampled data. Head RF receiver coil suitable for high performance, accelerated (i.e. GRAPPA, SENSE and Simultaneous Multislice or Multiband) imaging. A high-end, dedicated image reconstruction computer incorporating software for advance image reconstruction algorithms A high-end host computer operator console for MRI protocol planning, scanner operations, and image storage and review. Customer available and configurable 10Gb network interfaces for data transfer on host and reconstruction computers. Trade-in and removal of Obsolete MRI equipment: The existing Siemens 7T Plus system, designated FMRIF 7TA (site functional location ID: 400-342363), will be available as trade- in value as part of the purchase. The obsolete system will be extracted and removed from the FMRIF Center as part of this purchase. Turnkey Installation: The purchase will include the turnkey installation of the new, replacement MRI system, including installation of the MRI system magnet, electronic equipment and system console; in-suite connections to the facility power and cooling supplies; and all construction necessary to bring the MRI system console and magnet rooms to meet environmental standards required for clinical and research usage in the NIH Clinical Center. Additionally, installation of the current system should not adversely affect the operational state of any other MRI systems in the facility at system handover. MRI Systems Training: The offeror shall provide on-site training to FMRIF staff in the operation of all hardware and software / applications that will be required for routine operation of the upgraded or replaced MRI Systems. The Contractor shall additionally -- 1 of 4 -- provide access to training in pulse sequence and reconstruction software development for staff involved in methods development. Salient characteristics The FMRIF/NIMH requires a 7T MRI system suitable for human patient studies with the following components: Actively shielded 7T superconducting magnet Local gradient system with: o Maximum gradient strength of at least 200 mT/m o Maximum slew rate of at least 900 T/m/s Radio frequency electronics and an operator console Vendor-specified documentation for non-significant risk for human subject scanning is required for this system. The characteristics needed for each component are given below. However, the vendor is encouraged to offer a system with best possible specifications, and the proposed enhancements will be considered and evaluated during the technical review of the quotations. 1. Magnet a. Superconducting and actively shielded magnet with a field strength of 7.0 T (Tesla). b. Field homogeneity (fully shimmed with superconducting and/or passive shims) less than 5 ppm peak-to-peak over a 25 cm diameter spherical volume (DSV) and a water spectral linewidth of less than 0.1 ppm full width half height (FWHH) over a 25 cm DSV. c. Drift of the main field less than 0.05 ppm/hour and 0.005 ppm/hour without/with field drift compensation, respectively. d. The magnet will employ zero boil-off technology. e. The system will include a switch to shut-off the main field quickly and safely in case of an emergency. The location of the switch is to be determined during system installation. f. Ramp time: The time required to ramp the magnet up and down to and from field following installation or service procedures will be specified by the vendor. A faster ramp time is preferred. 2. Room temperature shim and gradient coils a. The room temperature active shim coil set should consist of at least 8 channels (3 first order and 5 second order terms) and a power supply. All room temperature active shims will be under computer control within the software environment used to run the rest of the console. b. The gradient amplifiers will be capable of generating at least 200 mT/m magnetic field gradient along each axis with a slew rate of at least 900 T/m/s with the system’s supplied coil. -- 2 of 4 -- c. The gradient waveform control unit should operate with at least 10 us time resolution, 16-bit amplitude resolution. d. The gradient field stability will be better than 0.5% at maximum gradient strength on each axis. e. The system will be equipped with a hardware/software mechanism to protect the gradients and gradient amplifiers from overheating. 3. RF Electronics a. Transmitter system i. The transmitter system will be capable of operating a parallel transmitter array, with eight independently controllable RF transmit channels capable of operating at frequencies suitable for protons. ii. RF transmit amplifiers should independently supplied at least 1 kW pulsed, linear, power on-resonance. iii. All RF channels will be driven by independent waveform generators with adequate waveform memory and capable of amplitude and phase modulation. iv. RF transmit power monitoring will be provided on all individual channels with an automatic mechanism to ensure that the estimated local and average SAR remains below the FDA/IEC guidelines. There will also be a system to limit the RF power to individual transmit elements. b. Receive…